Abstract
Nematodes of the genus Macropostrongyloides inhabit the large intestines or stomachs of macropodid (kangaroos and wallabies) and vombatid (wombats) marsupials. This study established the relationships of seven species of Macropostrongyloides using mitochondrial (mt) protein amino acid sequence data sets. Phylogenetic analyses revealed that species of Macropostrongyloides (M. lasiorhini, M. baylisi, M. yamagutii, M. spearei, M. mawsonae and M. woodi) from the large intestines of their hosts formed a monophyletic assemblage with strong nodal support to the exclusion of M. dissimilis from the stomach of the swamp wallaby. Furthermore, the mitochondrial protein-coding genes provided greater insights into the diversity and phylogeny of the genus Macropostrongyloides; such data sets could potentially be used to elucidate the relationships among other parasitic nematodes of Australian marsupials.